In engines with a large number of cylinders, two electronic control devices are often used, which are each assigned to a first and/or a second cylinder bank of the engine. The two control devices can access measurement data independently of one another, said data relating to the engine position as well as to additional measured values concerning the separate cylinder bank in each instance. One of the two control devices is usually defined as the master control device, which evaluates the actuation of the accelerator pedal in the motor vehicle for instance. The two control devices are connected to one another by way of a communication path, for instance a CAN bus.
DE 10 2006 030 592 A1 discloses a method for operating at least two engine control devices which are connected to one another in a master/slave configuration. Two control devices are provided in this way, which each execute a function for the internal combustion engine, which includes functions with angular synchronism which are attuned to the rpm of the engine. The same sensor system data of the identified engine position is available to the two control devices. When sending a command relating to a function with angular synchronism from the master control device to the slave control device, additional information representing the momentary engine position is also sent. The slave control device uses this information together with the momentary engine position provided upon receipt of this information in order to execute its function with angular synchronism to the master slave device.
In various instances a synchronization of the functions which run on the two control devices is necessary. Certain functions may in this way only run on one control device since otherwise a mutual interference would occur.